Hydrostatic holding devices have been used for a number of years to hold work parts which are to be machined or ground. Similarly, U.S. Pat. No. 5,516,243 discloses a cutting tool holder with an elongate, contracting hydrostatic sleeve to grip a shank of a tool during use. A chuck which receives the tool holder may have a second hydrostatic sleeve which is separately and independently actuated to hold and locate the tool holder. Each hydrostatic sleeve is actuated by a separate screw plunger threaded in a recess and threadably displaced to pressurize a fluid within a chamber adjacent the sleeve.
For many years conventional tool holding collets with mechanically actuated gripping fingers have been utilized in a wide variety of applications. However, there is still a need for hydrostatic tool and workpiece holding collets and particularly a hydrostatic collet insertable in a conventional mechanical collet carrier body.